"Religious institutions in America have long been free to determine their own beliefs and practices, and (Warren) does not think we should require them to conduct same-sex marriages in order to maintain their tax-exempt status," campaign spokeswoman Saloni Sharma said when asked about O'Rourke's remarks.

Warren is the latest Democratic presidential hopeful to create distance from O'Rourke's suggestion. Pete Buttigieg, mayor of South Bend, Ind., criticized the idea to CNN on Sunday.